When an older dog starts peeing more than usual, it almost always signals a medical issue rather than a behavior problem. The most common causes in senior dogs are chronic kidney disease, Cushing’s disease, diabetes, urinary tract infections, and medication side effects. Some of these are manageable conditions your dog can live with for years, while others need prompt treatment.
How to Tell If It’s Actually Too Much
It can be hard to know whether your dog is truly peeing more or just having more accidents. The distinction matters. A dog producing larger volumes of urine more frequently is dealing with something different than a dog who simply can’t hold it anymore. If your dog is also drinking noticeably more water, emptying the bowl faster than usual or seeking out toilets, puddles, or other water sources, that pairing of increased thirst and increased urination is a strong signal that something metabolic is going on.
Before your vet visit, try tracking how much water your dog drinks in a 24-hour period. You can use a measuring cup to fill the bowl and check what’s left at the end of the day. Graduated water bowls with volume markers are also available. This is trickier in multi-pet households, but even a rough estimate gives your vet useful information.
Chronic Kidney Disease
This is one of the most common reasons older dogs start peeing excessively. As the kidneys lose function with age or disease, they become less efficient at filtering waste from the blood. The body compensates by pushing more blood through the kidneys to try to keep up, which produces more urine. Your dog then drinks more to replace the lost fluid. It’s a cycle: failing kidneys cause more peeing, more peeing causes more drinking.
The tricky part is that kidney disease can be well underway before you notice anything wrong. The earliest detectable sign is dilute urine, which only shows up on a lab test. Newer blood markers can flag declining kidney function before the more traditional blood tests catch it. By the time a dog is visibly peeing and drinking more, a significant portion of kidney function has already been lost. That said, many dogs with chronic kidney disease live comfortably for months or years with dietary changes and supportive care, especially when it’s caught early.
Cushing’s Disease
Cushing’s disease is the most common hormonal disorder in older dogs, typically showing up between ages 7 and 12. It happens when the body produces too much cortisol, the stress hormone. Excess cortisol directly interferes with the hormone that tells the kidneys to conserve water. The result is that your dog’s kidneys essentially stop concentrating urine, producing large volumes of very dilute pee.
Dogs with Cushing’s often have a cluster of symptoms beyond the peeing: a pot-bellied appearance, thinning skin, hair loss (especially on the trunk), panting, and an almost insatiable appetite. If your older dog is peeing constantly and also looks like they’re developing a belly despite no change in food, Cushing’s is worth investigating. It’s manageable with daily medication, though it requires regular monitoring.
Diabetes
In diabetic dogs, the body can’t move sugar from the blood into cells properly, so blood sugar rises. Once it exceeds roughly 180 mg/dL, the kidneys can no longer reabsorb all that glucose, and it spills into the urine. Sugar in the urine pulls extra water along with it through osmosis, creating large volumes of urine. The dog then drinks heavily to keep up.
Excessive urination is often one of the first things owners notice. Other early signs include increased appetite despite weight loss, and cloudy or sticky-looking urine. Diabetes in dogs is typically managed with insulin injections, and most owners get comfortable with the routine quickly. Untreated, it can lead to serious complications including cataracts and a life-threatening condition called diabetic ketoacidosis.
Urinary Tract Infections and Uterine Infections
A bladder infection creates a persistent, urgent feeling of needing to pee. Your dog may go out frequently and produce only small amounts of urine, sometimes with visible blood or a strong odor. This is different from the large-volume urination of kidney disease or diabetes, where each trip produces a flood. A dog with a urinary infection knows they’re urinating and feels the urgency. They may whimper, strain, or have accidents near the door because they simply couldn’t wait.
For intact (non-spayed) female dogs, there’s an additional concern: pyometra, a serious infection of the uterus. As the uterus fills with bacteria and pus, toxins can leak into the bloodstream and affect kidney function, causing increased thirst and urination. Pyometra is a veterinary emergency. If your unspayed older female dog is peeing more and also seems lethargic, has a fever, or shows vaginal discharge, this needs same-day attention.
Medication Side Effects
If your senior dog takes corticosteroids (commonly prescribed for allergies, arthritis, or immune conditions), increased urination is a predictable and very common side effect. Steroids interfere with the kidneys’ ability to concentrate urine in the same way Cushing’s disease does, because the mechanism is identical: excess cortisol, whether the body makes it or it comes from a pill. Diuretics and some anti-seizure medications can have similar effects.
This doesn’t mean the medication needs to stop, but it’s worth a conversation with your vet about dose adjustments or alternatives if the peeing is severe enough to disrupt your dog’s life (or yours). Don’t stop any medication on your own, since some drugs require gradual tapering.
Incontinence vs. Increased Urination
These two problems look similar from your perspective (more pee in the house) but are fundamentally different. A dog with increased urination is producing more urine and knows when it’s going. A dog with incontinence is leaking urine involuntarily, often while sleeping or resting, and may not be aware it’s happening. You might find wet spots where your dog was lying down, or notice damp fur around their back end.
Incontinence in older dogs, especially spayed females, is frequently caused by weakening of the urinary sphincter as hormone levels decline with age. This is very treatable with medication that strengthens sphincter tone. It’s a quality-of-life issue rather than a sign of serious internal disease, so if the wet spots are the main symptom and your dog otherwise seems healthy, this may be the explanation.
Cognitive Decline
Dogs can develop a condition similar to dementia in humans. One of the hallmark signs is house-soiling in a dog that was previously reliable about going outside. But this isn’t really about producing more urine. It’s about forgetting the rules, not recognizing the signal to go out, or getting confused about where they are. You might also notice your dog staring at walls, getting stuck in corners, seeming disoriented at night, or failing to recognize familiar people.
Your vet will want to rule out the medical causes listed above before attributing accidents to cognitive decline, since many of the symptoms overlap. Blood work and a urine test can quickly separate a metabolic problem from a neurological one.
What Your Vet Will Look For
Expect the appointment to involve blood work and a urine sample at minimum. The urine test reveals how well the kidneys are concentrating urine, whether glucose is spilling over (pointing to diabetes), and whether infection is present. Blood tests check kidney waste products, blood sugar, and markers that can flag Cushing’s disease or other hormonal problems. Your vet will also want a complete medication history, since some drugs make the urine test harder to interpret.
Bring your water-intake observations and note when the increased peeing started, whether it came on suddenly or gradually, and whether there are other changes like appetite shifts, weight changes, or lethargy. A sudden onset suggests infection or a new medication reaction. A gradual increase over weeks or months points more toward kidney disease, Cushing’s, or diabetes. These details help your vet narrow down the possibilities quickly and avoid unnecessary tests.